Safety device for railway car door operating mechanism



Jam, 1?, 19% A, E, ZEM ER mwm SAFETY EVICE FOR RAILWAY CAR DOOR ERATINGMECHANISM Filed Feb. 12, 1945 immifl art. 2/777 er INVENTOR PatentedJan. 17, 1950 UNITED STATES OFF ICE SAFETY DEVICE FOR RAILWAY CAR. DOOR.OPERATING MECHANISM Albert E. Zimmer, Chicago, Ill.,.:assignor toEnterprise Railway Equipment Company; Chicago, Ill., acorporationofIllinois Application February-12, 1945; sens-1N0. 577,463

My invention relates to improvements in load discharging cars of thetype shown in the patent toArgyle Campbell, No. 2,197,237., issued April16; 1-940, and particularly to the door operating mechanism. One of theobjects of the invention is to provide a safety means to prevent theaccidental locking of the ratchet mechanism to the'winding mechanismshaft during the opening of the doors and the resultant danger of injuryto the operator.

Other objects will appear hereinafter.

My inventionconsists-inthe provision of means in connection with thepawl and ratchet mech anism for rotating the shaft for preventing thepawl from being accidentally thrown into engagement with the ratchetwheel while the shaft is being rotated at great speed by: the doorsopening under the weight of the load;

' My invention further consists in the combination and arrangement ofparts hereinafterde scribed and set forth' in the appended claims. Theaccompanying drawing illustrates one embodiment of the invention. 7

. Fig.1 is a sideelevation' of a pawl and ratchet mechanism associatedwith the door operating mechanism shaft;

Fig. 2 is a vertical transverse sectional view substantially on. theline 22 of Fig. 1; and

Fig. 3 is an enlarged top or plan view of the mechanism shown in-Figs.1- and 2.

- Railway load discharging cars of the type shown insaid hereinheforementioned patent have dumping-doors in their. bottom for discharge ingthe load-by gravity. These doors arehinged at one side and are supportedat their other sideloy linkage which is wound upon or unwound from an.operating shaft when the doorsare swung to closed or open position. Thislinkage is of the self-locking type which looks the doors in closedposition by the rotation of the shaft in; the direction to wind thelinkage upon the shaft. When the shaft rotates in the other direction,the linkage unwinds from the shaft and allows the doors to swingdownwardly to open position.

The shaftv A is positioned along the side of the car and is extended tothe end of the car where it is provided with a ratchet mechanism B.which enables the operator to manually rotate;

the shaft. This mechanism is provided with a socket i for the receptionof a long removable handle bar C which provides sufiicient leverage forthe operator. The socket or handle bar mem ber comprises'in general twowall members 2' and .6 Claims; (01.. it-157.)

3 which are freely rotatable independently of theshaft uponahubmember 4which is secured or-locked tothe shaftzA, the-shaft and the bore of thehub being squared in section for this purpose-. The-wall members arespaced apart by spacing' lugs 5' and 'fi and secured in rigid assemblyby the rivets "l and 8 which extend through the spacing lugs.

Bet-ween thewall members, the hub 4 is protitled with a series of teethEl which form a ratchet wheel adapted to beengaged by a pawl member H),also positioned between the wall members 2- and 3 above the ratchet. Thepawl is pivotally mounted on the upper spacing lug 5-, being providedwith a hub H which surrounds the said lug. The pawl is in the form of ashort arm having a flat end l2 for engagement with the teethof theratchet. These parts are so proportioned that thepawl, when inengagement with the ratchet teeth, is disposed at an angle to' a centerline through the pivotal axis of the pawl and the center of the shaft A,so that the pawl can be positioned by the operator in engagement with:the ratchet teeth, on either side of thisacenter line. depending uponwhich direction theoper'ator desires to rotate the shaft. The pawlisplacedi in either:- of these positions "by swinging orrotating it inan arc'about its pivotal axis, as indicated by the broken line I3 (Fig.2). If the operator desires to close the doors, he swings the pawl tothat side of the center line which-corresponds'to the rotation of theshaft which winds up the linkage mechanism. If the operatordesirestoopen the doors, he places the pawl on that side of; the'line inthe direction o'f retation' of the shaft for unwinding the linkage. .Inthis caseyhe need only rotate the; shaft sufficiently tolunlock thelinkage mechanism,

whereupon: the. weight of the load on the door causes: the doors to dropwith great force and rapidity and completes the. unwinding of thelinkagevmechanism and? rotates the shaft in the same direction athighspeed. This disengages the pawl fromsther ratchet tooth which it happensto-bevengaging by being struck and swung outwardly by following teeth onthe ratchet. It may happen, however, that the pawl is struck with suchforce that it will be swung about its pivot completely through the arcto the other side-oi the center: line, whereupon it may engage a ratchettpoth. and cause the, member B and the-handle bar C to rotate with theshaft with such suddenness andiiorce asto injure the opera ator.

In accordance with. my." invention, I providea means associated with theratchet mechanism, which acts to retard or even stop the swing of thepawl about its pivot to the other side of the center line. In thepresent structure, this retarding means consists of a round protuberanceor cam l4 formed at the upper end of the wall member 2 and positioned inthepath of'the side l5 of the pawl II! when it is swung-in a planeperpendicular to the rivet I and surroundin spacing lug 5 on beingstruck a sharp blow by one of the teeth 9 of the ratchet wheel. It willbe understood that the pawl ID will swing in this manner because of thecentrifugal force imparted thereto by such a blow which causes the innersurface portion I6 of the opening through the hub ll opposite the flatend I 2 to engage and slide over the outer surface ll of the spacing lug5. Since these surfaces [6 and H are disposed at right angles to thewallmembers 2 and 3, the pawl i and particularly the side IE will swingfreely in a plane parallel thereto and the cam [4 will be engaged by oneedge or the other of the side l depending upon the direction that thepawl I6 is thrown.

In order to permit the pawl Ill to be swung manually past the cam l4 theformer is mounted loosely on its pivot provided by the spacing lug 5with a substantial clearance between the surfaces IB and I! as indicatedat l8. This clearance l8 permits the pawl Hi to be canted by theattendant relative to the spacing lug 5 sufficiently to move the side l5clear of the cam l4 and thereby permits the pawl ill to be swung fromone operative position to the other depending upon the direction inwhich the shaft A is to be rotated.

I claim:

1. In a railway dump car door operating mechanism, a shaft rotatable ineither direction for operating said mechanism to open or close thedoors, a ratchet mechanism on said shaft including a handle bar formanually rotating said shaft, a pawl for said ratchet mechanism movablemanually to either of two positions depending upon the direction inwhich the shaft is to be rotated, and means to prevent the pawl frombeing thrown from one position to the other when the shaft is rotated bythe opening of the doors under load said means including a fixed cammember fixed relative to the axis of rotation of said pawl and adaptedto be engaged by the moving pawl to retard the pawl prior to itsreaching said other position.

2. In a railway dump car door operating mechanism, the combination of anoperating shaft for said mechanism rotatable in either direction, aratchet mechanism for manually rotating the shaft in either direction,said ratchet mechanism including an oscillating member rotatableindependently of the shaft and having a handle bar for the operator, atoothed ratchet on the shaft, a pawl carried by the oscillating memberadapted to engage the teeth of the ratchet in either of two positionsdepending upon the direction in which the shaft is to be rotated, and afixed cam member carried by and fixed on said oscillating member andadapted to be engaged by the pawl in its movement from one position tothe other to retard the movement of the pawl.

3. In a railway dump car door operating mechanism, the combination of ashaft rotatable in either direction for operating said mechanism, aratchet mechanism including a handle bar for manually rotating the shaftin either direction, said ratchet mechanism comprising a pair of spacedmembers mounted to oscillate on said shaft, a toothed ratchet wheel onthe shaft positioned between said spaced members, a pawl pivotallymounted between said spaced members to swing in said space about itspivot in an arc to either of two positions for engagement with the teethof said ratchet wheel, and a projection on one of said spaced memberspositioned to reduce the space to a minimum sufficient to allow the pawlto pass the space in its movement from one position to the other.

4. In a railway car door operating mechanism of the type including ashaft, a toothed ratchet wheel secured to said shaft, at least onemember abutting said ratchet wheel and mounted for oscillatory movementupon said shaft, and a pivotally movable pawl mounted adjacent saidmember and carried by said member to swing about its pivot in an arc toeither of two positions for engagement with the teeth of said ratchetwheel, retarding means adapted to retard the swing of the pawl about itspivot from one of its two positions to the other, said retarding meanscomprising a cam integrally formed in said member, and a cam-engagingface on-the pawl, the pawl being so positioned that in normal operationthe cam-engaging face will engage the cam but will still permit manualmovement of the pawl beyond the cam.

5. In a railway car door operating mechanism of the type including ashaft, a toothed operating ratchet wheel secured to said shaft, 2. pairof spaced members mounted to oscillate on said shaft and abutting saidtoothed ratchet wheel on either side thereof, and a pawl pivotallymounted between said spaced members to swing in said space about itspivot in an arc to either of two positions for engagement with the toothof said ratchet wheel, retarding means adapted to retard the swing ofthe pawl about its pivot from one of its two positions to the other,comprising an immovable projection integral with one of said spacedmembers and so positioned to reduce the space between said spacedmembers to a minimum sufficient to allow the pawl to pass the space inits movement from one position to the other, whereby the pawl may bemanually moved beyond said projection but will be stopped by saidprojection in normal operation.

6. In a railway car door operating mechanism wherein a shaft rotatablein either direction to open or close the door is provided having aratchet wheel secured thereto for rotating the same, in combination, awall member rockably mounted on said shaft adjacent said ratchet wheeland adapted to be rocked manually thereabout to rotate said shaft, apawl rotatably mounted on said wall member about an axis parallel'tosaid shaft for movement to either of two operative positions on oppositesides of a line through the axes of said pawl and shaft depending uponthe direction in which the latter is to be rotated to place said wallmember in driving relation to said shaft, said pawl being likely to beswung to the opposite position by being struck a blow by a tooth of saidratchet wheel on rotation thereof in the same direction that it is beingdriven by said pawl, and a fixed cam on said wall member in the path ofsuch movement of said pawl adapted to be engaged thereby to prevent itsmovement to its other operative position, said pawl being looselymounted on its pivot whereby it can be canted manually with respectthereto surfieientlyfar to clear seid cap for manual UNITED STATESPATENTS shlftmg to lts other operatlve posmon.

ALBERT E. ZIMMER. Number Name Date 827,235 Hackney July 31, 1906REFERENCES CITED 5 906,624 Hackney Dec. 15, 1908 The followingreferences are of record in the 114O167 Kolb et a1 May 1915 file of thispatent:

